Today, most of electronic equipments such as computer and communication equipment are installed with heat dissipation fans to meet the heat dissipation needs of the system and to ensure the stability of the system. Currently, usually a device for controlling heat dissipation fan directly controls speed regulation for a fan through a control signal when monitoring and regulating speed of the fan, this method of directly and electrically connecting with the fan through a control signal has considerable risks and shortcomings, when an equipment works unstably or malfunctions during the power up, the fan cannot be controlled effectively, making the status of the fan uncontrollable, for example: the fan stops or the rotating speed of the fan is slow, and the heat dissipation of the equipment cannot be met, resulting in overheating damage of key chips in the equipment.